Valve for percussive tools.



Patented. Feb. 2, 19

M NUM/EY VALVE FOR PERCUSSIVE TOOLS.

APPLICATION FILED JUIE l, 1914.

"Wis 'VE 2^ ein new" n :lil i nl mi'tfroremen, for iiereusive Quels. el' .vhiexi she 'f is is. speeiezitien.

This .im'enii/h reim' 1s mires im. permissive tools, uml mere pai'xicuhxrly im mh" 1 of the type thrown hy compressiun genen :ile/(l in the Cylinder h5* the iston :it the emi nl is stroke in eilher directimi.

The Objee or; this .invention is izo prm'ide :i vulve meehnriishi which will he simple er' construcin aml'he se lmlsneed thai :i very slight degree ivf emi'ipressimi in he eiu'ls mi: the -Lfylihder is reigiiired *w threw iheizher direction. i

With this ehi@ in View, :i vulve medirshisiii hais been d h zi @Sicil einhmliment 0i whieh repreixsenieil in the secure lmlrring (lrmvihgs, in whieh,

ligures l :md shew lengritiuli'zrril ses tiens through the level wi'ch the fe meel mism and piston iii lii'leren pesimms.

lh the nlrmrinw's, the tool is shown :as eem prising' a cylinder l in which reeiprmnes a. Neer the freut end 0E the CarlinN is :i valve her il while uvm' lie haul; mui. nl he cylinder is n valve here 4, 'Frein the extreme 'mw rel v end er ,i1-he eylimler mi 'mlell peri 5 opens into the frenieiifjl e? the valve here while from the rear end wf the cylinder a cylinder inlet peri; 6 epens hat() the rear emi ef lie valve here l. lli-(m1 :i point in the cyliner some (lis'hnee erher from the from end than the pori :i eyliii der exhaus port T @pei s to the faire here 3 through :i port 8 in he renr uml of the valve here. slightly smaller in lifiiiieer thm: she Valve here while from :i point further from the rear end of the cylinder than 'Lhe- .port 6 a. Cylinder exhaustport 9 opens o the frontend of the valve bore il lirough :i port 'l0 in the freut end of the vulve bore 4 of smaller diameter than the Valve here. To 'the side 0lA the 'zilve here 3 a` sligl'it distance rearward of 'the port. :i vulve here inle passage ll leads from the fluid iiile per 12 of the toohy while to the side of he valve here l :i slgh (llsmee forward of 'he pori 6 a valve here inlet passage 1B also lencls 'from kshe inlet pom l! of the mol. From the here rightly greater fli'er fhu i ihe L l 6,] il' :my disincen heile. The vnl-.fe l is slightlv longer "he disearse heb orward. ege

` rez'rwsril elige Alzirly., lhe veli e L distance lie-larve in vulves auf,

if@ w i ,l i vr ise l l, similarly, when @he valve est position the other one will he also. v v

in epers'ien, sirppesing the' parts se he the pesiiens slmwn in Fig. l? +he sir *A exilim* thrmifrh the port l? and passage l the iurwnrd end ei" :the *alive here 37 ''.hrmijfh the peri: im@ he 'erwf'irl enel e? he ejfliriler. and moving the gisten rem'- wsrilijf. The air from ibhe rear r portieri rf the eyinfler will exhaust through he por?, sphe- A e begin Lhe iceriini'd face el the valve 16 'faire mechanism `will he positively tained in warmest pesition. As the piszmi mores rearwardly the first change in the pressure eonditiens on the valves will come when the from fue@ of the piston passes the port 7. This will allow live pressure to pass tp the port. 8 and almostv hala-nee the live pressure en the for 'ard end of the valve 1G. This port S is, however, made slightly' smaller in diameter than the valve bore 3. en that there will he u slight excess of effective pressure on the lower end of thevalve 16, maintaining the valve mechanism in fixed position until it is necessary for 'it to be thrown. Shortly after th?` forward end of the piston passes the port lrhe rear car l communicated to the rearward face o the.

ward end of the piston will cover the port 9, thus cutting off the exhaust from the rear end of the cylinder. As soon as this occurs pressure will commence building up in the rear end of the cylinder from the momentum of the piston, this pressure being valve 17 through the port 6. As the only pressure on the valve at .this time is due to the slight difference in area of the port 8 and the front face of the valve 16, the piston will have to travel only a very short distance before suicient pressure is generated to throw the valve 17 forwardly, carrying with ,lt the valve 16, through the agency of the rod 18. This position of the parts is shown in Fig. 2. The method of operation on the forward stroke of the piston is merely the reverse of thatl lready described and .need not be further tailed.

It will be evident that since the valves are each separately balanced by pressure on their ends, it is immaterial what their rela .tive diameters are. It is preferable, however, to have 'the rearward valve of a little greater diameter so that the valve will throw slightly more quickly at the end of the rearward stroke.

Although 'for simplicity of construction the valves 16 and 17 are shown in separate pieces operated from eachother by' means of the rod 18, it is evident that they could be attached together if desired, and it is to he understood that while the present showing and description discloses only one speciiied modicatlon of the invention, other forms and modifications are included inthe vspirit and scope of the invention as expressed 1n the claims.

at points more distant from the ends of the valve bores than their respective cylinder inlet and exhaust ports, and means to move one valve from the other.

3. Ina fluid operated percussive tool, a cylinder, a piston, a valve mechanism for each end of the cylinder, comprising valve hores, cylinder inlet ports leading from the ends of the cylinder to ends of the valve bores, cylinder exhaust ports leading from points farther from the ends of the cylinder than said cylinder inlet' ports to the other ends of said valve bores, inlet and exhaust ports leading to and from said valve bores at points more distant from the ends of the valve hores than their respective cylinder inlet and exhaust ports, valves sliding in said valve bores and controlling the said valve bore inlet and exhaust ports, and means to -moveV one valve from the other comprising a 'spacing rod between sald valves.

4. In a iuid operated percussive tool, a cylinder, a piston, valve mechanism for each end of the cylinder comprising valve bores, cylinder inlet ports leading from the ends of the cylinder to ends of eachv of the valve bores, cylinder exhaust ports leading from pointsfarther from the ends of the cylinder than said cylinder inlet ports to ports at the other ends of the valve bores, said Orts be# ing of smaller. diameter than said valve bores, valve bore inlet and exhaust ports leading to and from the sides of said valve bores, valves sliding in said valve bores and controlling said inlet and exhaust ports, and means to move one valve from the other.

In 'testimony whereof, have hereunto set my hand,

- LEWIS C. BAYLES. Witnesses:

FRED. M. SLATER, ARTHUR SMITH. 

